Step 3: The weight of my gold
Scrap gold is valued by weight. It doesn't matter how fine or expensive the piece was when you bought it. All we are going to do is melt it down and extract the gold.
How close do I need to be?
Pretty close. Most jewelry is pretty light. You will probably be dealing in a few grams of gold.
What unit of measurement should I use?
It really doesn't matter, as long as you can do the math and convert it to Troy ounces. You probably won't have a scale that will weigh in Troy ounces or pennyweights, so standard ounces or grams are probably what you'll use.
We use grams - actually down to tenths of a gram - since it's easy to work with.
Common measurements, and their conversions:
- Grams. There are 31.1 grams in a Troy ounce.
- Standard ounce. There are 28.3 grams in a standard ounce, so it's a little bit lighter than a Troy ounce.
- Troy ounce. This is the basic unit of measurement in gold. Prices are quoted in Troy ounces.
- Pennyweight. This is an archaic jeweler's measurement. There are 20 pennyweights in a Troy ounce. If a buyer will only quote you by the pennyweight, they are probably trying to confuse the issue. Move on.
Determine how much gold is in each pile
Multiply the grams by the percentage for each karat and add up the results.
Example: 15 grams of 10KT and 10 grams of 14KT
15 grams 10KT X .417 = 6.3 grams of gold
10 grams 14KT X .583 = 5.8 grams of gold
6.3 + 5.8 = 12.1 grams of gold